diff --git a/aos/linux_code/configuration.cc b/aos/linux_code/configuration.cc
new file mode 100644
index 0000000..6c39a93
--- /dev/null
+++ b/aos/linux_code/configuration.cc
@@ -0,0 +1,105 @@
+#include "aos/linux_code/configuration.h"
+
+#include <string.h>
+#include <errno.h>
+#include <stdlib.h>
+#include <sys/types.h>
+#include <netinet/in.h>
+#include <arpa/inet.h>
+#include <ifaddrs.h>
+#include <unistd.h>
+
+#include "aos/common/logging/logging.h"
+#include "aos/common/unique_malloc_ptr.h"
+#include "aos/common/once.h"
+
+namespace aos {
+namespace configuration {
+namespace {
+
+// Including the terminating '\0'.
+const size_t kMaxAddrLength = 18;
+
+// TODO(brians): Don't hard-code this.
+const char *const kLinuxNetInterface = "eth0";
+const in_addr *DoGetOwnIPAddress() {
+  ifaddrs *addrs;
+  if (getifaddrs(&addrs) != 0) {
+    LOG(FATAL, "getifaddrs(%p) failed with %d: %s\n", &addrs,
+        errno, strerror(errno));
+  }
+  // Smart pointers don't work very well for iterating through a linked list,
+  // but it does do a very nice job of making sure that addrs gets freed.
+  unique_c_ptr<ifaddrs, freeifaddrs> addrs_deleter(addrs);
+
+  for (; addrs != NULL; addrs = addrs->ifa_next) {
+    if (addrs->ifa_addr->sa_family == AF_INET) {
+      if (strcmp(kLinuxNetInterface, addrs->ifa_name) == 0) {
+        static const in_addr r =
+            reinterpret_cast<sockaddr_in *>(__builtin_assume_aligned(
+                addrs->ifa_addr, alignof(sockaddr_in)))->sin_addr;
+        return &r;
+      }
+    }
+  }
+  LOG(FATAL, "couldn't find an AF_INET interface named \"%s\"\n",
+      kLinuxNetInterface);
+}
+
+const char *DoGetRootDirectory() {
+  ssize_t size = 0;
+  char *r = NULL;
+  while (true) {
+    if (r != NULL) delete r;
+    size += 256;
+    r = new char[size];
+
+    ssize_t ret = readlink("/proc/self/exe", r, size);
+    if (ret < 0) {
+      if (ret != -1) {
+        LOG(WARNING, "it returned %zd, not -1\n", ret);
+      }
+      LOG(FATAL, "readlink(\"/proc/self/exe\", %p, %zu) failed with %d: %s\n",
+          r, size, errno, strerror(errno));
+    }
+    if (ret < size) {
+      void *last_slash = memrchr(r, '/', size);
+      if (last_slash == NULL) {
+        r[ret] = '\0';
+        LOG(FATAL, "couldn't find a '/' in \"%s\"\n", r);
+      }
+      *static_cast<char *>(last_slash) = '\0';
+      LOG(INFO, "got a root dir of \"%s\"\n", r);
+      return r;
+    }
+  }
+}
+
+const char *DoGetLoggingDirectory() {
+  static const char kSuffix[] = "/../../tmp/robot_logs";
+  const char *root = GetRootDirectory();
+  char *r = new char[strlen(root) + sizeof(kSuffix)];
+  strcpy(r, root);
+  strcat(r, kSuffix);
+  return r;
+}
+
+}  // namespace
+
+const char *GetRootDirectory() {
+  static aos::Once<const char> once(DoGetRootDirectory);
+  return once.Get();
+}
+
+const char *GetLoggingDirectory() {
+  static aos::Once<const char> once(DoGetLoggingDirectory);
+  return once.Get();
+}
+
+const in_addr &GetOwnIPAddress() {
+  static aos::Once<const in_addr> once(DoGetOwnIPAddress);
+  return *once.Get();
+}
+
+}  // namespace configuration
+}  // namespace aos